Automatic inflating device



June 16, 1953 G. H. coNNoRs 2,642,110

AUTOMATIC INFLATING DEVICE 2 Sheets-Sheet l Filed March l1, 1949 i y gm INVENToR.

BY KM 9L June 16, 195,3 G, H, CNNQRS 2,642,110

AUTOMATIC INFLATING DEVICE 2 Sheets-Sheet 2 Filed March 11, 1949 Patented June 16, 1953 2,642,110 AUTOMATIC INFLATING DEVICE George H. Connors, Edgerton, Wis., assigner to Highway Trailer corporation Company, Edgerton, Wis., a

Application March 11, 1949, Serial No. 80,940 2 Claims.Y (C1. 152-421) The object of my to produce an improved construction of automatic tire infiator unit to be used for inflating the tires of automotive vehicles, and especially useful in conjunction with tires of heavy trucks, trailers and like vehicles. My invention however, is adapted for use in conjunction with smaller vehicles and is therefore not limited to the heavier .class of vehicles first above referred to.

Automatic tire inflators have long been known in the art but as. heretofore constructed have embodied certain objectionable-features that have largely caused discontinuance of their use. The principal objections to the automatic inflators of the prior art have arisen due to the fact that the pumping means of the iniiator when installed required continuous operation thereof during the traveling movement of the vehicle. In the prior inators provision was appropriately made whereby the air pumped to the tire under normal iniiating conditions would be by-passed into the atmosphere after a tire or tires were inflated to the predetermined pressure required for normal operation. But when the said predetermined pressure was reached the mechanism of the prior tire inflators would continue to operate the pumping means thereby producing wear on the moving parts such as to greatly shorten the life of the same.

Another objection to the automatic tire infiators of the prior art resides in the fact that the construction thereof was mounted between the spokes of steel wheels in such a manner that the cam follower at the lower end ofl the pump piston would ride on a cam located on the axle spindle midway between the inner and outer spindle bearings.v Such construction cannot be used to any large extent today because of the trend of automotive vehicle construction requiring the adoption of disc wheels so generally in use time, thus making the location of the automatic tire inflator or pumping means, as heretofore availed of impossible.

Still another objection to the prior art inflating units of the type referred that the axle lubricant in many instances would enter the tires by way of the pump, thus rendering ythe operative action ofthe former constructions entirely objectionable Von this particular account.

Reference is made to constructions ,suchV as shown in U. S, Patent #1,792,123 in conjunction' with the above description of the former type of automatic tire inflator once generally used and which has been made obsolete for reasons present invention has beenv such that they werev above stated as well as having the objectionable features recited.

In the carrying out of I have endeavored to provide a construction `of tire inflating unitvadapted to be applied to discwheels ofY the type generally in use today and which eliminate the objectionable features of construction and operation to which I have referred above,

A full understanding of my improvements of the present invention and the construction and merits thereof, will be following detailed description in conjunction with the accompanying drawing in which:

Figure 1 is a fragmentary sectional view showing the customary automotive construction equipped with an automatic tire inflator embodying my invention, the arrangement of the tires upon the wheel and the connection between the automaticv pumping vmeans for carrying the inflating air' from the latter to the tires being clearly shown.

The hub portion and retaining nut section is on line I-I of Figure 2.

Figure 2 is a fragmentary View in elevation of certain parts illustrated in Figure 1 looking toward the outer side of the pumping unit.

Figure 3 is a vertical sectional view through the body of the pumping unit.

Figure 4 is a view in elevation showing primarily the parts illustrated in Figure 3 looking toward the unit of Figure 3 from a direction at the left of said unit. 1

to involved the hazard Figure 5 is a detailed sectional View taken on about the line 5--5 of Figure 4 looking in the direction of the arrows.

Figure is a detailed sectional view taken on about the line of 6--6 of Figure 4 looking in the Figure 'T is a fragmen' direction of the arrows. tary sectional view showing the construction of the upper portion of Figure 3 with the lock pin for holding-the pumping piston out of operation, disengaged from said piston, as compared with Figure 3 vin which said lock pin is interengaged or interlocked with the piston to hold it against being Vcontinuously operated during the travel movement of the wheel,-after the tires are fullyA inflated.

Figure 8 is a view in detail showing a little moreV clearly the construction of the cam nut on the outer end of the axle spindle by which nut the roller follower on the pumping piston is moved to reciprocate the piston to produce its pumping' action during the tire nating operation of the unit.

It will be understood that the disc wheel A as my invention therefore had upon reference to thev Van ordinary type of dual disc steel wheel of shown in my drawings is of a conventional type such as commonly in use today. It is equipped with the usual rims B, that support the tires C in the customary manner for removal and replacement. The wheel A is mounted upon the spindle E by means of the usual hub D and the outer end of the spindle E is threaded as customary, as shown at E. The threaded portion of the spindle E in the ordinary disc wheel construction such as shown in the drawings receives the usual type of nut, prior to the installation of the pumping unit of my invention,

Now in carrying out my invention the hub D of the wheel A is held on the axle in the usual manner, but for this purpose I employ a nut I at the outer end of Which is provided aneccentric cam portion, such nut being substituted for the nut that is commonly found on and employed for attaching the disc wheel A to the spindle E. In other words the cam nut of my invention performs the usual function of retaining the Wheel on the spindle but in addition thereto it provides an actuator for the pumping unit to be later set forth. The nut I as seen in the draw-Yv ings is held in place against movement by the usual lock washer 2, one outer lip 2a of which is bent into a slot in the hub of the nut I, another outer lip 2b of the washer being bent into a slot in the inner nut Ia, and the inner lip or key 2c of the washer being seated in the keyway on the spindle E.

The tire inflating pumping unit G of my invention Vis mounted upon a special hub cap I-I which houses the outer end of the nut I and lies in a plane about vertically central of the outer rim B and tires C mounted thereon.

The pumping unit generally designated G comprises a piston cylinder S in which is mounted the piston II, the piston rod I2 of which is of poly-sided or square formation so as to pass through a square opening in a partition I2@ intermediate the ends of the cylinder 9,. the piston rod I'Z being guided in the partition I2a and being prevented from rotating by reason of the cross sectional formation of the piston rod and the opening in the partition IZa.

A spring ID encircles the portion of the piston rod I2 at the side of the partition IZa opposite that on which the piston I I itself is disposed and said spring I@ bears at one end against the adjacent side of the partition I2a and at the opposite end against the end Wall of the piston member 8 remote from the piston head I I. The piston head I I is the pumping piston of the pumping unit and the piston 8 is a guiding piston body equipped at the end thereof remote from the partition Ia with a follower roller 3. The normal action of the spring ID is to force the piston body 8 toward the cam nut I and maintain the follower roller 3 :against the eccentric outer portion of the nut I, as well as to produce the suction movement of the piston head II coincidental with the movement of the piston body The relation between the follower roller 3 and the eccentric portion of the nut I is maintained constant because the piston rod I2 is prevented from turning in its `bearing portion at the partition I2a, as indicated above. Movement of the piston head II in the suction direction caused by the action of the spring I will draw air through an air cleaner 5 mounted on hub cap H to which pumping unit G is secured. An air pipe I leads from the cleaner 5 to the intake valve I3 located in a passage in the head at the outer end of the pumping unit G designated ISa. In this manner the air is drawn into the cylinder 9 and as the piston I I travels in the outward radial direction of its movement, or compression direction said air is forced into the tires C past a check valve I4 in said head I3a, the air passing through an angular passage 9a formed in the parts 9 and I3a and entering a chamber I5 located on the inner side of the pumping unit and suitably formed in the integral body of the cylinder member S. From the chamber I 5 the air passes to pipes I5 leading from opposite sides of the chamber I5, one of the pipes being connected to the outer tire C and the other of said pipes being connected to the inner tire C.

In the chamber I5 there is located a pressure actuated locking pin I'I which is connected to a diaphragm Ila fixed to the peripheral wall of 'the chamber I5 and adapted to flex inwardly yand outwardly. The pin Il' is adapted to enter and move out of a recess I8 located in the outer peripheral wall of the piston body 8.

Around the pressure actuated locking pin II is a specially calibrated spring I'Ib which controls the action of said pin in a manner to be later described in conjunction Vwith the operation of the diaphragm Ila.

Seen best in Figure 5 of the drawings the head ISUJ at the outer end of the piston unit cylinder 9 is provided with an outlet valve 2li the spring 20a of which is calibrated to compress at a pressure slightly greater than that required to fully inflate the tire and the. purpose of this valve 20 will appear more fully hereinafter. The said valve is arranged to control passage of air from the cylinder Si on compression strokes of the piston II by reason of the arrangement of the Valve 2li in conjunction with the passage 20h, which passage leads from the valve passage itself to the `atmosphere to the upper end of the piston cylinder 9.

Having in View the construction of my automatic tire inating unit as before presented, I will now describe the operation of the mechanism under ordinary conditions of use.

It will be apparent from the mounting of the pumping unit including the cylinder 9, upon the wheel of A, that the said unit and the two conduits or pipes I6 will rotate with the wheel so that the camkfollower or roller 3 follows around the cam or eccentric portion of the nut I causing the piston 8 and its connected piston head II to reciprocate back and forth in the cylinder 9, the

nut I producing the compression stroke by thel action of the rise of the cam on the nut I acting on the roller 3, the spring Ill producing the suction stroke incident to forcing the piston head I I in the direction of the partition Iza der As the piston I I travels in the suction direction the air is drawn through the air strainer 5 into the cylinder 9 through the intake valve I3 and as the piston head I I travels in the compression or outwardly radial direction of its movement the said air is forced into the tires by passing through the passage 9a, by the check valve I4, into the chamber I5 and through the pipes or conduits I6 to the tires. When the tires are inflated to the desired pressure equal pressure is present in chamberrfl. At such time and under such pressure condition the pin I'I will be forced into the in the cylingroove I3 of the piston body 8 and will hold stationary said piston body and its connected piston head II, at the end of the compression stroke as long as this full ination pressure in the tires is maintained. Of course when the pin I l' interlocks in the groove I8 of the member 8 the fol- :mospherel Vvalve I4.

' unnecessary to continue the operation of thev pumping means, and

it is highly desirable that the moving parts cease their operation to avoid the wear and tear incident to the latter when the pumping means is not desired to function for further inflation purposes. The spring I'Ib is so calibrated as to compress at the predetermined desired high pressure so as to effect the interlocking of the pin I'I with the member 8 to stop the operation of the pumping means and the pressure in the tires acts through the diaphragm I'Ia upon the pin I1 and the spring I'Ib to control the foregoing action when pressure in the tires C lowers beyond the point at which the maximum pressure isdesired to be maintained, the spring I1b will withdraw the pin I1 from the groove I8 of the piston body 8 and the pumping operation of the piston head II will be resumed incident to the reciprocating movement of the parts 8 and I I induced by the cooperative action of the spring IIJ and the rolling contact of the follower member 3 on the nut I.

The valve 2G is a safety valve as it controls the passage of air through the passage 20D, from within the outermost portion of the cylinder 9 at the outer side of the piston head I I. The safety valve 20 aords protection against over-inflation of the tires C, the springs 20a of said valve being calibrated to compress at a pressure slightly greater than that required for maximum pressure ination of the tires.

Under this condition, if for any reason pumping is not stopped by the arresting of the movement of the reciprocating piston parts 8 and I I, incident to improper action .of the lock pin II, the valve 20 Will openand the air being pumped, in excess of the amount required to provide the predetermined normal pressure in the tires C, will exhaust into the at- A spring The ease of mounting of my pumping unit upon the wheel and axle is of importance to my invention. The parts of my invention are so constructed as to facilitate the foregoing phase yof the invention.

It is notable also that I employ the common or conventional form of commercial oil seal designated 4 as seen in my drawing in contact with the concentric hub portion of the cam nut I and this oil seal i will efflectively prevent any of the axle lubricant from entering the pump and ultimately being pumped into the tires C.

Screw bolts h are employed to attach the hub cap I-I to the adjacent outer end of the hub D of the wheel A.

Y Having thus described my invention, what I Illa coacts with the check.

` pumping member, an air conduit y pumping member, an

claim as new and desire to secure by Letters Patent of the United States, is:

1. In combination, a wheel, axle means supportingsaid wheel, a pneumatic tire on the wheel, an automatic pumping unit comprising a movable connecting the unit-to the tire to supply inlating air to the latter, means mounting the said unit on the wheel to turn therewith, an instrumentality on the axle means to actuate the movable pumping member as the wheel rotates on the axle means, mounting means comprising a hub cap for an end of the axle means and housing said instrumentality, bearing means between the axle means and the wheel, 'and a lubricant seal between the bearing means and the pumping unit. l

2. 1n combination, a wheel, axle means supporting said wheel, a pneumatic tire on the wheel, an automatic pumping unit comprising a movable air conduit connecting the unit to the tire to supply inflating air to the latter, means mounting the said unit on the wheel to turn therewith, an instrumentality on the axle means to actuate the movable pumping member Y as the wheel rotates on the axle means, and mechanism including a diaphragm mounted in a chamber of the unit, said chamber being connected by the air conduit aforesaid to the tire, and said diaphragm being provided with a locking member the presence of the air in the tire effecting actuation of said diaphragm and member controlled by the pressure of the air in the tire for incapacitating the pumping member when the air pressure in the tire reaches a predetermined amount, to prevent over inflation of the tire, the mounting means for the pumping unit kcomprising a hub cap for the axle unit and the actuating instrumentality comprising a nut for attaching the wheel to the axle means, antifriction bearings are provided between the wheel at its hub portion and the axle means, and a lubricant seal is interposed between the hub cap and the nut arranged to seal the pumping unit from the passage of lubricant thereto from the bearings.

GEORGE H. CONNORS.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,265,211 Keith May 7, 1918 1,278,387 Risk Sept.,10, 1918 1,288,826 Cahill Dec. 24, 1918 1,358,524 Cooper Nov. 9, 1920 1,517,782 Harper Dec. 2, 1924 1,792,123 Rymal Feb. 10, 1931 1,804,192 Wilson May 5, 1931 2,231,812 Long et al. 1 Feb. l1, 1941 2,317,636 Parker Apr. 27, 1943 2,415,618 West Feb. 11, 1947 Said 

